package medium;
/*
82. 删除排序链表中的重复元素 II
 */
public class LeeCode82 {

  public static void main(String[] args) {

  }

  public ListNode deleteDuplicates(ListNode head) {

    if (head == null) {
      return head;
    }

    ListNode pre = new ListNode(0, head);
    ListNode cur = pre;
    while (cur.next != null && cur.next.next != null) {
      if (cur.next.val == cur.next.next.val) {
        int x = cur.next.val;
        while (cur.next != null && cur.next.val == x) {
          cur.next = cur.next.next;
        }
      } else {
        cur = cur.next;
      }
    }
    return pre.next;
  }

  class ListNode {
    int val;
    ListNode next;
    ListNode() {}
    ListNode(int val) { this.val = val; }
    ListNode(int val, ListNode next) { this.val = val; this.next = next; }
  }
}
